Vehicle fuel supplying apparatus

ABSTRACT

A fuel supplying apparatus for a vehicle for supplying fuel including an in-tank type fuel pump  7  provided in a sub-tank  5  inside a main tank  1  and a tubular fuel holding case  21  surrounding a suction filter portion  20  of this fuel pump  7  and having an opening portion  21 B which is open in an opposite direction to a forwardly moving direction of the vehicle, so as to supply fuel  2  to outside the main tank  1  through a delivery pipe  16  by means of the fuel pump  7.  The fuel  2  can be supplied to an engine even during the quick braking of the vehicle when the amount of fuel  2  is small without increasing the number of component parts of the apparatus.

TECHNICAL FIELD

The present invention relates to a fuel supplying apparatus for avehicle of an in-tank type in which a fuel pump is incorporated in afuel tank, and more particularly to a fuel supplying apparatus for avehicle which is capable of supplying fuel even when the vehicle isbraked quickly.

BACKGROUND ART

FIG. 7 is a side cross-sectional view illustrating a conventional fuelsupplying apparatus for a vehicle disclosed in, for example, JapaneseUtility Model Examined Publication No. 37178/1989. In FIG. 7, referencenumeral 1 denotes a main tank for storing fuel 2, 1 a denotes a bottomwall of the main tank 1, and 1 b denotes a bottom wall opening providedin the bottom wall 1 a of the main tank 1. Numeral 3 denotes a settingplate which is oil-tightly attached to the bottom wall opening 1 b bymeans of bolts 15 through packing 4.

A sub-tank 5 which is inserted in the main tank 1 is provided on aninner surface 3 a of the setting plate 3, and an in-tank type fuel pump7 which is attached by a pump holder 6 is provided on an inner bottomsurface 5 a of the sub-tank 5. FIG. 8 is an enlarged perspective view ofa suction filter portion of the fuel supplying apparatus for a vehicleshown in FIG. 7. In FIG. 8, numeral 8 a denotes an opening portionconnected to an inlet port 7 a (located inside the fuel pump 7 in FIG. 7and is invisible) of the fuel pump 7, 8 b denotes a screen portion forfiltering the passing fuel 2, and 8 c denotes a protector for preventingthe rubbing against each other of the screen portion 8 b and the innerbottom surface 5 a of the sub-tank 5.

The sub-tank 5 is attached to prevent the fuel 2 from not being suppliedto an unillustrated engine from the fuel pump 7 when the vehicle body isinclined in a state in which the amount of fuel 2 in the main tank 1 hasbecome small. A discharge port 7 b of the fuel pump 7 is connected to amain tube 10 by means of a rubber hose 9. The main tube 10 is bentdownward, is oil-tightly passed through the setting plate 3, and isconnected by a joint 14 to a delivery pipe 16 directed to theunillustrated engine. Further, a power supply line 11 having one endconnected to a connector 12 outside the main tank 1 has its other endoil-tightly passed through the setting plate 3 and connected to a powersupply terminal 13 of the fuel pump 7.

Next, a description will be given of the supply of the fuel 2. A voltageis applied from the power supply terminal 13 through the connector 12and the power supply line 11 to drive the fuel pump 7, which in turncauses the fuel 2 in the main tank 1 to be sucked from the suctionfilter 8, and after the fuel 2 is pressurized by the fuel pump 7, thefuel 2 passes through the main tube 10 and is supplied to the deliverypipe 16 directed to the unillustrated engine.

However, with the above-described conventional fuel supplying apparatusfor a vehicle, since the sub-tank 5 is cup-shaped with its upper surface5 b open, during quick braking when the acceleration acting in thevehicle becomes maximum the fuel inside the sub-tank 5 rides over theupper surface 5 b of the sub-tank 5 and flows to outside the sub-tank 5.For this reason, there has been a problem in that when the amount offuel 2 in the main tank 1 has become small, the fuel 2 fails to besupplied to the unillustrated engine by the fuel pump 7.

The present invention has been devised to overcome the above-describeproblem, and its object is to obtain a fuel supplying apparatus for avehicle which is capable of supplying fuel to the engine even when thevehicle is braked quickly.

DISCLOSURE OF THE INVENTION

In accordance with the present invention, a fuel supplying apparatus fora vehicle for supplying fuel, by means of an in-tank type fuel pumpprovided in a fuel tank, to outside the fuel tank through a pipeconnected to the fuel pump, comprises: fuel holding means having anopening portion which is open in an opposite direction to a forwardlymoving direction of the vehicle and formed so as to hold a predeterminedamount of fuel in a vicinity of a fuel inlet portion of the fuel pumpduring the quick braking of the vehicle.

Further, the opening portion has a guide portion for guiding the fuel tothe fuel holding means during the quick braking of the vehicle.

Further, the fuel holding means is a tubular case surrounding the fuelinlet portion of the fuel pump.

Further, a portion of the fuel holding means is disposed between thefuel tank and a suction filter portion provided in the fuel inletportion of the fuel pump.

Furthermore, the fuel holding means is arranged such that a portion of asealing member for sealing a gap between a setting plate, on which thefuel pump is disposed, and the fuel tank is formed in a concave shapefor covering the fuel inlet portion of the fuel pump.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side cross-sectional view of a fuel supplying apparatus fora vehicle in accordance with a first embodiment of the presentinvention;

FIG. 2 is an enlarged perspective view of packing of the fuel supplyingapparatus for a vehicle shown in FIG. 1;

FIG. 3 is an enlarged perspective view of a suction filter of the fuelsupplying apparatus for a vehicle shown in FIG. 1;

FIG. 4 is a side cross-sectional view of the fuel supplying apparatusfor a vehicle in accordance with another embodiment of the presentinvention;

FIG. 5 is a side cross-sectional view of the fuel supplying apparatusfor a vehicle in accordance with still another embodiment of the presentinvention;

FIG. 6 is an enlarged perspective view of packing (sealing member) ofthe fuel supplying apparatus for a vehicle shown in FIG. 5;

FIG. 7 is a side cross-sectional view illustrating a conventional fuelsupplying apparatus for a vehicle; and

FIG. 8 is an enlarged perspective view of a suction filter portion ofthe fuel supplying apparatus for a vehicle shown in FIG. 7.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereafter, a description will be given of the embodiments of the presentinvention. FIG. 1 is a side cross-sectional view of a fuel supplyingapparatus for a vehicle in accordance with a first embodiment of thepresent invention. In FIG. 1, reference numeral 1 denotes a main tank(fuel tank) formed of, for instance, a steel plate and for storing fuel2, 1 a denotes a bottom wall of the main tank 1, and 1 b denotes abottom wall opening provided in the bottom wall 1 a of the main tank 1.Numeral 3 denotes a setting plate which is formed of, for instance, asteel plate and is oil-tightly attached to the bottom wall opening 1 bby means of bolts 15 through packing (sealing member) 4. FIG. 2 is anenlarged perspective view of the packing of the fuel supplying apparatusfor a vehicle shown in FIG. 1. In FIG. 2, reference numeral 4 a denotesa hole through which the bolt 15 is passed, and 4 b denotes a holethrough which a sub-tank (fuel tank) 5, a main tube 10, and a powersupply line 11 are inserted.

The sub-tank 5 which is inserted in the main tank 1 is provided on aninner surface 3 a of the setting plate 3, and an in-tank type fuel pump7 which is attached by a pump holder 6 is provided on an inner bottomsurface 5 a of the sub-tank 5.

The sub-tank 5 is attached to prevent the fuel 2 from not being suppliedto an unillustrated engine from the fuel pump 7 when the vehicle body isinclined in a state in which the amount of fuel 2 in the main tank 1 hasbecome small. A discharge port 7 b of the fuel pump 7 is connected to amain tube 10 by means of a rubber hose 9. The main tube 10 is bentdownward, is oil-tightly passed through the setting plate 3, and isconnected by a joint 14 to a delivery pipe 16 directed to theunillustrated engine. Further, a power supply line 11 having one endconnected to a connector 12 outside the main tank 1 has its other endoil-tightly passed through the setting plate 3 and connected to a powersupply terminal 13 of the fuel pump 7.

FIG. 3 is an enlarged perspective view of a suction filter portion ofthe fuel supplying apparatus for a vehicle shown in FIG. 1. In FIG. 3,numeral 20 denotes a suction filter portion (fuel inlet portion of thefuel pump 7), 20 a denotes an opening portion connected to an inlet port7 a (located inside the fuel pump 7 in FIG. 1 and is invisible) of thefuel pump 7, and 20 b denotes a screen portion for filtering the passingfuel 2. Numeral 21 denotes a fuel holding case (fuel holding means)which is attached to the suction filter portion 20 by means ofunillustrated screws and is formed of a synthetic resin, such as nylon,in a tubular case shape. The fuel holding case 21 has a main bodyportion 21A surrounding the screen portion 20 b of the suction filterportion 20 and for holding a predetermined amount of fuel 2 in thevicinity of the suction filter portion 20 b during the quick braking ofthe vehicle; an opening portion 21B which is open in an oppositedirection to the forwardly advancing (the direction of arrow A) of thevehicle; and a guide portion 21C for guiding the fuel 2 into the fuelholding case 21 during the quick braking of the vehicle. This fuelholding case 21 also has the function of a protector for preventing therubbing against each other of the screen portion 20 b and the innerbottom surface 5 a of the sub-tank 5.

Here, the forwardly advancing of the vehicle generally means thedirection in which the driver faces the front. In addition, the mainbody portion 21A suffices if it has such an arrangement and a structurethat it is capable of holding a predetermined amount of fuel 2 in thevicinity of the suction filter portion 20 b during the quick braking ofthe vehicle, and capable of supplying the held fuel 2 to a suctionfilter portion 8 at least in an amount which can be sucked by the fuelpump 7. In addition, the opening portion which is open in an oppositedirection to the forwardly advancing of the vehicle suffices if it isarranged such that the opening plane formed by the opening portion 21Bcan be at least seen from the opposite direction to the forwardlyadvancing of the vehicle. In other words, this means that thearrangement may be such that the opening plane of the opening portion21B, when viewed from the opposite direction to the forwardly advancingof the vehicle, is inclined. However, the arrangement in which, as shownin FIG. 1, the opening plane of the opening portion 21B is substantiallyorthogonal to the opposite direction to the forwardly advancing of thevehicle is preferable in view of the efficiency with which the fuel 2 isheld and because effective use can be made of the limited space in thesub-tank 5. In addition, although a description has been given of theexample in which the fuel holding case 21 is fixed to the suction filterportion 20 by means of the screws, this fixation may be fixation basedon an adhesive agent, fixation based on ultrasonic welding, or fixationbased on press fitting. Meanwhile, the fuel holding case 21 may beformed integrally on the suction filter 20. As shown in FIG. 3, if thefuel holding case 21 and the suction filter portion 20 are formedseparately, the fuel holding case 21 can be replaced. Further, the fuelholding case 21 in accordance with the present invention can be attachedto an existing fuel driving apparatus for a vehicle. In addition,although the fuel holding case 21 shown in FIG. 3 is arranged so thatonly the opening portion 21B is open, it suffices if the fuel holdingcase 21 is arranged to be capable of holding the fuel 2 during the quickbraking of the vehicle, and openings other than the opening portion 21Bmay be provided in the main body portion 21A.

Next, a description will be given of the supply of the fuel 2. A voltageis applied from the power supply terminal 13 through the connector 12and the power supply line 11 to drive the fuel pump 7, which in turncauses the fuel 2 in the main tank 1 to be sucked from the suctionfilter portion 20, and after the fuel 2 is pressurized by the fuel pump7, the fuel 2 passes through the main tube 10 and is supplied to thedelivery pipe 16 directed to the unillustrated engine. Then, when thevehicle is braked quickly in a state in which the amount of fuel 2 hasbecome small, even if the fuel 2 in the sub-tank 5 rides over an uppersurface 5 b of the sub-tank 5 and flows to outside the sub-tank 5, thefuel 2 which can be sucked by the fuel pump 7 still remains in the fuelholding case 21, so that the fuel 2 is supplied to the delivery pipe 16directed to the unillustrated engine.

With the fuel supplying apparatus for a vehicle constructed as describedabove, when the vehicle is braked quickly in the state in which theamount of fuel 2 has become small, even if the fuel 2 in the sub-tank 5rides over the upper surface 5 b of the sub-tank 5 and flows to outsidethe sub-tank 5, the fuel 2 which can be sucked by the fuel pump 7remains in the fuel holding case 21, so that the fuel 2 can be suppliedeven during the quick braking of the vehicle.

In addition, since the guide portion 21C is provided for guiding thefuel 2 to inside the fuel holding case 21 during the quick braking ofthe vehicle, the fuel 2 can be reliably moved to and held in the fuelholding case 21.

In addition, since the fuel holding case 21 is a tubular casesurrounding the suction filter portion 20 of the fuel pump 7, there ispractically no risk of causing damage to the screen portion 20 b whenthe fuel pump 7 is assembled to the main tank 1 in the state in whichthe fuel holding case 21 is attached to the suction filter portion 20.

In addition, since the fuel holding case 21 also has the function of theprotector for preventing the rubbing against each other of the screenportion 20 b and the inner bottom surface 5 a of the sub-tank 5, thereis no possibility of causing damage to the screen portion 20 b, and thenumber of component parts does not increase.

In addition, since the fuel holding case 21 has the structure of atubular case, as compared with a conventional protector 8 c (FIG. 7) thefuel holding case 21 has large mechanical strength against vibrations,deflection in the vertical direction (axial direction of the fuel pump7) of the main tank 1, and the like, so that its thickness can be madesufficiently small as compared with the conventional protector 8 c (FIG.7). Accordingly, it becomes possible to dispose the screen portion 20 bat a position closer to the bottom surface of the sub-tank 5, i.e., at alower position in the sub-tank 5, so that the fuel 2 can be supplied tothe unillustrated engine until the level of fuel 2 becomes much lower.

Furthermore, as for the fuel holding case 21, a description has beengiven of the case in which the length, as viewed in the advancingdirection of the vehicle, of the tubular case surrounding the suctionfilter portion 20 for the fuel pump 7 is substantially the same as thelength of the screen portion 20 b, and yet it suffices if the fuelholding case 21 has such a length that a predetermined amount of fuel 2can be held therein. This being the case, however, it is preferred thatthe length of the tubular case in the advancing direction of the vehiclebe substantially the same as the length of the screen portion 20 bbecause the fuel holding case 21 can also demonstrate the protectorfunction and because damage to the screen portion 20 b can be preventedwhen the fuel pump 7 is built in the main tank 1.

Next, a description will be given of another embodiment of the presentinvention. FIG. 4 is a side cross-sectional view of the fuel supplyingapparatus for a vehicle in accordance with another embodiment of thepresent invention. In FIG. 4, a main tank 22 has a concavely shapedportion 22 b in which a portion of a bottom wall 22 a of a main tank 22is shaped in a concave shape, and the suction filter portion 20incorporating the fuel holding case 21 is built inside this concavelyshaped portion 22 b. Since the other arrangements are similar to thoseof the foregoing embodiment, a description thereof will be omitted. Byusing the concavely shaped portion 22 b of the bottom wall 22 a of themain tank 22 and the fuel holding case 21, the vessel (sub-tank 5 inFIG. 1) can be disused, the number of component parts can be curtailed,and it is possible to obtain advantages similar to those of theabove-described first embodiment.

Next, a description will be given of still another embodiment of thepresent invention. FIG. 5 is a side cross-sectional view of the fuelsupplying apparatus for a vehicle in accordance with still anotherembodiment of the present invention. FIG. 6 is an enlarged perspectiveview of packing (sealing member) of the fuel supplying apparatus for avehicle shown in FIG. 5. In FIGS. 5 and 6, the main tank 22 has theconcavely shaped portion 22 b in which a portion of the bottom wall 22 ais shaped in a concave shape, and an opening 22 c is provided in thebottom wall 22 a of this concavely shaped portion 22 b. Numeral 23denotes packing (sealing member) which is attached to the aforementionedopening 22 c with a seal portion 23 d being clamped by the setting plate3 and the main tank 22. Numeral 23 a denotes a hole through which thebolt 15 is passed, 23 b denotes a hole through which the pump holder 6,the main tube 10, and the power supply line 11 are inserted. Numeral 23c denotes a fuel holding portion (fuel holding means) which covers ascreen portion 8 b of the suction filter 8 and is open in the oppositedirection to the forwardly advancing (the direction of arrow A) of thevehicle. Since the other arrangements are similar to those of theforegoing embodiments, a description thereof will be omitted.

With the fuel supplying apparatus for a vehicle constructed as describedabove, since the fuel 2 which can be sucked by the fuel pump 7 can bepooled inside the fuel holding portion 23 c, it is possible to use theconventional suction filter portion 21, and the fuel 2 can be heldwithout an increase in the number of component parts. In addition, sincethe fuel holding portion 23 c of a size corresponding to the insidediameter of the packing 23 can be formed, the fuel holding portion 23 ccan be made large, so that the fuel 2 can be reliably supplied to theunillustrated engine during the quick braking of the vehicle.

It should be noted that the fuel supplying apparatus for a vehicle ineach embodiment described above can be applied to both four-wheeled andtwo-wheeled vehicles, but is useful particularly for a two-wheeledvehicle for the following reason. The reason is that since the engine isdisposed on the front side (front side in the forwardly moving directionof the vehicle), the fuel pump 7 is frequently disposed rearwardly ofthe center of the main tank 1 so as to avoid the effect of heat from theengine.

In addition, since the structure provided such is that the fuel holdingcase 21 is provided in the sub-tank 5 or the concavely shaped portion 22b, the fuel 2 held in the fuel holding case 21 or the fuel holdingportion 23 c is spread to become level inside the sub-tank 5 or theconcavely shaped portion 22 b after the quick braking of the vehicle, sothat the fuel 2 can be held efficiently by a compact fuel holding case21. If the sub-tank 5 or the concavely shaped portion 22 b is notprovided, the fuel 2 held in the fuel holding case 21 or the fuelholding portion 23 c is spread to become level inside the main tank 1after the quick braking of the vehicle, so that a very large fuelholding case 21 or fuel holding portion 23 c becomes necessary.

Industrial Applicability

The fuel supplying apparatus for a vehicle in accordance with thepresent invention is provided with the fuel holding means having anopening portion which is open in an opposite direction to the forwardlymoving direction of the vehicle and formed so as to hold a predeterminedamount of fuel in the vicinity of a fuel inlet portion of the fuel pumpduring the quick braking of the vehicle. Therefore, the fuel can besupplied to the engine even when the vehicle is braked quickly in astate in which the amount of fuel has become small.

Further, since the opening portion has a guide portion for guiding thefuel to the fuel holding means during the quick braking of the vehicle,the fuel can be held reliably.

Further, since the fuel holding means is a tubular case surrounding thefuel inlet portion of the fuel pump, the mechanical strength is high andthe apparatus can be made compact.

Further, since a portion of the fuel holding means is disposed betweenthe fuel tank and the suction filter portion provided in the fuel inletportion of the fuel pump, it is possible to prevent he suction filterportion from striking the bottom wall of the fuel tank, and thepossibility of the suction filter portion becoming damaged at the timeof attachment of the fuel pump is reduced further.

Furthermore, since the fuel holding means is arranged such that aportion of a sealing member for sealing a gap between the setting plate,on which the fuel pump is disposed, and the fuel tank is formed in aconcave shape for covering the fuel inlet portion of the fuel pump, thefuel can be supplied to the engine even when the vehicle is brakedquickly without an increase in the number of component parts.

What is claimed is:
 1. A fuel supplying apparatus for a vehicle forsupplying fuel, by means of an in-tank type fuel pump provided in a fueltank, to outside said fuel tank through a pipe connected to said fuelpump, comprising: fuel holding means having an opening portion which isopen in an opposite direction to a forwardly moving direction of thevehicle and formed so as to hold a predetermined amount of fuel in avicinity of a fuel inlet portion of said fuel pump during the quickbraking of the vehicle.
 2. The fuel supplying apparatus for a vehicleaccording to claim 1, wherein said opening portion has a guide portionfor guiding the fuel to said fuel holding means during the quick brakingof the vehicle.
 3. The fuel supplying apparatus for a vehicle accordingto claim 1, wherein said fuel holding means is a tubular casesurrounding said fuel inlet portion of said fuel pump.
 4. The fuelsupplying apparatus for a vehicle according to claim 3, wherein aportion of said fuel holding means is disposed between said fuel tankand a suction filter portion provided in said fuel inlet portion of saidfuel pump, and an axial direction of said tubular case is disposed alongsaid fuel tank.
 5. The fuel supplying apparatus for a vehicle accordingto claim 3, wherein said opening portion has a guide portion for guidingthe fuel to said fuel holding case during the quick braking of thevehicle.
 6. The fuel supplying apparatus for a vehicle according toclaim 1, wherein said fuel holding means is arranged such that a portionof a sealing member for sealing a gap between a setting plate, on whichsaid fuel pump is disposed, and said fuel tank is formed in a concaveshape for covering said fuel inlet portion of said fuel pump.
 7. Thefuel supplying apparatus for a vehicle according to claim 1, whereinsaid opening portion is defined in a vicinity of a bottom surface ofsaid fuel tank.
 8. The fuel supplying apparatus for a vehicle accordingto claim 1, wherein said fuel holding means is closed except for saidopening portion.
 9. The fuel supplying apparatus for a vehicle accordingto claim 1, further comprising a suction filter portion provided in saidfuel inlet portion of said fuel pump, wherein said fuel holding means isat least as long as said suction filter portion.
 10. The fuel supplyingapparatus for a vehicle according to claim 1, further comprising asub-tank disposed within said fuel tank, wherein said fuel tank has aconcave shaped portion and said fuel holding means is disposed withinone of said sub-tank and said concave shaped portion.